Re: [PATCH v2 4/4] swiotlb: Free tbl memory in swiotlb_exit()

[Konrad Rzeszutek Wilk]

On Sat, Jul 31, 2021 at 11:26:11AM -0700, Guenter Roeck wrote:
> Hi,
> 
> On Tue, Jul 20, 2021 at 02:38:26PM +0100, Will Deacon wrote:
> > Although swiotlb_exit() frees the 'slots' metadata array referenced by
> > 'io_tlb_default_mem', it leaves the underlying buffer pages allocated
> > despite no longer being usable.
> > 
> > Extend swiotlb_exit() to free the buffer pages as well as the slots
> > array.
> > 
> 
> This patch causes qemu pseries emulations to crash. Backtrace and bisect
> log see below. Reverting it fixes the problem.

I am 99% sure it is fixed by this patch (which should be in linux-next
in 5 minutes):